The present invention relates to a new and distinct cultivar of Corylus plant (hazelnut, filbert), botanically known as Corylus avellana, and hereinafter referred to by the name ‘Red Dragon’.
The new Corylus resulted from a controlled cross of female parent OSU 487.055 and male parent OSU 367.039 made in 1997 by Shawn A. Mehlenbacher and David C. Smith. Neither parent was protected by a plant patent. Hybrid seeds from the cross were harvested in August 1997, stratified, and seedlings grown in the greenhouse during the summer of 1998. From this cross, 42 seedlings with contorted growth habit were planted in the field in October 1998. ‘Red Dragon’ was discovered and selected by the inventors as a single plant within the progeny of the stated cross-pollination in a controlled environment in Corvallis, Oreg., USA. It was originally assigned the designation OSU 897.078, which indicates the row and tree location of the original seedling.
The female parent OSU 487.055 is from a cross of ‘Contorta’×VR 6-28 (which is a cross of ‘Riccia di Talanico’×‘Gasaway’), and the male parent OSU 367.039 is a red-leaf selection from open-pollination of ‘Contorta.’ The presumed pollen parent of OSU 367.039 is the red leaf cultivar ‘Rode Zeller’ (syn. ‘Rote Zellernuss’), which has a dominant allele at the leaf anthocyanin locus. A tree of ‘Rode Zeller’ was near the ‘Contorta’ tree from which open-pollinated nuts were collected. ‘Red Dragon’ and OSU 487.055 carry in heterozygous state a dominant allele for complete resistance to eastern filbert blight (EFB) from ‘Gasaway.’ Contorted growth habit is conferred by a recessive allele from ‘Contorta’ (syn. Corylus avellana var. contorta).
The new cultivar was asexually reproduced by rooted suckers (tie-off layerage of the suckers) annually for three years (2003–2005) in Corvallis, Oreg. and harvested in late November to early January. The layers of ‘Red Dragon’ were moderately vigorous, and rooted with a higher frequency and produced more roots than most other contorted selections. Asexual reproduction was also performed by whip grafting in Corvallis, Oreg. in late spring 2004. ‘Red Dragon’ has been grafted on each of four rootstocks, namely: ‘Barcelona,’ ‘Mortarella,’ ‘Dundee,’ and ‘Newberg.’ ‘Red Dragon’ is also suitable for propagation by micropropagation. The unique features of this new Corylus are stable and reproduced true-to-type in successive generations of asexual reproduction.